While temporary storage in the garage is fine for chilly nights, your begonias need a permanent indoor growing location … Growing begonias from their seeds, which are as fine as dust, takes time and careful handling. A comprehensive guide for growing begonias from seed indoors. Choose a warm, humid, partly sunny indoor spot for your begonias. Remember that if you save the seeds from your hybrid begonias, you won’t get baby plants that look … A young plant will erupt from tissue along the leaf veins and then … Save money and fill your summer shade gardens with masses of beautiful begonias. This how to guide teaches the care requirements for growing tuberous and fibrous begonias indoors without a greenhouse. Propagating a Polka dot Begonia Maculata ‘Wightii’ Make a Leggy Plant more Bushy. Etiolation is the official name for when your plant gets leggy, with long stems and lots of space in between each leaf, caused by too little light.. Another common reason for spindly Begonias … Summer is the ideal time to take leaf cuttings from your houseplants and begonias propagate well from leaf cuttings.